Simplified Design Calculation Schemes for Machine Tool Mechanisms

Simplified Design Calculation Schemes for Machine Tool Mechanisms

was unknown. The influence of the side rake angle on the width of flake, cutting force, and the damage of the cutting edge of the tool was investigate...

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was unknown. The influence of the side rake angle on the width of flake, cutting force, and the damage of the cutting edge of the tool was investigated. Graphs, Photomicrographs. 103, V. K. Kulik, A. M. Pedchenko, "Simplified Design Calculation Schemes for Machine Tool Mechanisms," Soviet Engineering Research, 9(5), pp. 81-86. (1989). Dynamic calculation procedures based on simplified schemes give an acceptable level of accuracy in the design of machine tool mechanisms, and at the same time reduce labor costs. In order to simplify the calculation scheme it is necessary to calculate partial and natural vibration frequencies, vibration forms and power characteristics of the mechanism. Simplification methods currently in use allow the designer to reduce the number of degrees of freedom of the model, and hence reduce the amount of calculation work, but not to find ways in which the design can be improved. The present article proposes a method of simplifying dynamic models. 7 Refs. 104, S. P. Velsko, C. Syn, B. A. Fuchs, D. B. Poker, C. Ortiz, "Single Point Diamond Turning of a Organic Nonlinear Crystal, L-arginine Phosphate," Materials Research Society, Optical materials: processing and science, Vol 152, San Diego, CA (USA), 24-26 Apr 1989. pp. 285-285. Materials Research Society. Pittsburgh, PA (USA). The authors have demonstrated that single point diamond turning can be used to generated high optical quality finished surfaces on a new organic nonlinear crystal, Larginine phosphate (LAP). The proper choice of cutting conditions can produce surfaces with less than 5 angstroms rms surface roughness. Local softening or melting near the cutting tool tip may play a key role in the machining process by ensuring that material is removed by ductile cutting rather than brittle fracture. At the same time, the low melting temperature of LAP makes lubrication and cooling especially important to prevent extensive melting and tool fouling. In spite of the presence of a weak cleavage plane in LAP, the surface quality is relatively insensitive to crystallographic orientation. Tool wear is apparently negligible, so that surface flatness is governed by the stability of the diamond turning machine. Data on residual subsurface strain and preliminary measurements of the optical damage thresholds of diamond turned LAP surfaces are presented. 105, R. Eade, "Softwares Brings Manufacturing Up to Speed," Cutting Tool Engineering, 42(7), pp. 18-20, 22, 24-26, 28. (Oct. 1990). As software programs become more powerful and easier to use, dramatic increases in productivity, profitability and speed of processing are being realized. A review of software currently available for manufacturers covers: CAD/CAM; milling; die making; adaptive machining; grinding; sawing; EDMing; roughing/finishing; Icons; and the future in software. A software program for die making applications can be used to make complicated sheet-metal (e.g. steel) parts, 3-D dimensioning and NC partprogramming. 106, H. S. Lee, Y. Furukawa, "Stiffness Design Method of Grinding Machine," Bulletin of the Japan Society of Precision Engineering, 24(2), pp. 136-141. (Jun 1990). Stiffness affects either a residual stock removal behavior and a self-excited chatter vibration, both of which are usually caused by the deflections of grinding wheel and work-support systems in ordinary grinding machine. Hence, the stiffness design method which makes the machine free from both behaviors with rational amount of static and dynamic stiffnesses is desired. The present paper proposes how much of the static stiffness should be included in order to obtain proper spark-out time for a residual stock removal. 9 Refs. 107, Y. G. Kabaldin, "Structural-energetic Approach to the Processes of Friction, Wear, and Lubrication in Cutting," Soviet Journal of Friction and Wear, 10(5), pp. 24-30. (1989). We present the results of theoretical and experimental studies of the mechanisms of hard-alloy wear in cutting. Electron microscope studies show that minimization of the hard-alloy tool wear intensity is intimately associated with the formation in its surface layers of energetically stable dislocation structures, which leads to an extremal nature of the dependence of the tool service life on the cutting speed. We indicate ways to improve the energetic stability and effectiveness of hard-alloy surface layers. 12 Refs. 108, H. Nakazono, H. Yasui, M. Kurusu, A. Hosokawa, "Studies on Dressing of the Resin-bond CBN Grinding Wheel (lst report). An Investigation of Cutting Edge Distribution," Bulletin of the Japan Society of Precision Engineering, 24(1), pp. 51-56. (Mar 1990). This report deals with the cutting edge distribution on the working surface of the resin bond CBN wheel formed by the dressing of WA stick method, which closely relates to the grindability of the wheel. The detailed observation of the cutting edge and the precise measurement of its distribution are carried out for various dressing conditions with the newly constructed equipment. The cutting edge distribution is formed by removing the bond materials along with various actions such as fracture, release and appearance of the CBN grains. The cutting edge distributes open with the consumption of WA stick for severer dressing conditions and becomes more close by the retruing operation just after dressing. Dressing and retruing operations make it possible to control the cutting edge distribution over a wide range. 5 Refs. 109, K. Syoji, L. Zhou, S. Matsui, "Studies on Truing and Dressing of Diamond Wheels (lst report). The Measurement of Protrusion Height of Abrasive Grains by Using a Stereo Pair and the Influence of Protrusion Height on Grinding Performance," Bulletin of the Japan Society of Precision Engineering, 24(2), pp. 124129. (Jun 1990). The protrusion height of abrasive grain in a metal bonded diamond wheel plays an important role in grinding performance. Low protrusion height, for example, promotes the loading and increases grinding force markedly. A wheel with large protrusion height, on the contrary, has a problem of attrition wear and releasing of cutting edges. However the precise measuring method adapted to the protrusion height has not been developed so far. In this paper, a new 3-dimensional measuring technique left bracket 3D method right bracket is proposed by using a SEM stereo pair. And the effect of magnitude of the protrusion height on a diamond wheel which is trued and dressed with a GC cup-truer is investigated experimentally on Si3N4 ceramic grinding. The main results obtained are presented. 3 Refs. 110, S. Hanasaki, M. Touge, "Study of the Electrolytic Grinding Mechanism Using a Single-Diamond Cutting Tool With a Wear Flat Area," Wear, 139(2), pp. 285-301. (Aug. 1990). Electrolytic single-diamond cutting was performed to determine the grinding mechanism of electromechanical grinding at a high work feed rate. Two types of single-diamond cutting tools

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